Brush head for a toothbrush and method for producing the brush head

ABSTRACT

The brush head of the toothbrush has filaments that are pointed at one end and led through clearances in the bristle carrier. These filaments have a length of about 10-20 mm. The tips of the pointed filaments produce a height profile other than that of a plane and the ends of the pointed filaments that are remote from the tips are melted.

This is Continuation application of U.S. patent application Ser. No.11/826,442 filed on Jul. 16, 2007, which is a Continuation-in-Part ofU.S. patent application Ser. No. 11/255,990 filed on Oct. 24, 2005 nowU.S. Pat. No. 7,419,225 issued on Sep. 2, 2008, which is a Continuationapplication of PCT Application No. PCT/CH2003/00263 filed in Switzerlandon Apr. 22, 2003. The disclosure of the prior applications is herebyincorporated by reference herein in their entirety.

BACKGROUND

The disclosure relates to a brush head for an electric or manualtoothbrush and to a method for producing such a brush head.

Electric toothbrushes usually have a handle, in which a motor isaccommodated, and a generally exchangeable brush head. A brush head witha bristle carrier which can be driven in a rotationally movable manneris known for example from DE-U 295 20 230. An electric toothbrush ofwhich the brush head is made to vibrate is disclosed by WO 01/28452.Furthermore, electric toothbrushes of which the brush heads perform apivoting movement about their longitudinal axis in the manner of arocker are also known, for example from CH 421 049. Known electrictoothbrushes have a brush head which is provided with clusters ofconventional bristles. These are rounded off at their end to avoidinjuries.

Manual toothbrushes with a bristle arrangement which entirely comprisespointed filaments are known for example from EP-A 0 596 633 and DE-U 9012 603. The pointed filaments serve for the handling or cleaning of finestructures in the surface of the tooth, for example fine cracks, whichcannot be effectively treated with conventional cylindrical bristles.Furthermore, thanks to the narrower tips, the pointed filamentspenetrate better into the spaces between the teeth and clean thembetter. Electric toothbrushes with pointed bristles are not known.

However, pointed bristles react poorly to mechanical abrasion in theregion of the tip. Under excessive mechanical loading, the tips of thesebristles break and may, on the one hand, no longer bring about thecleaning effect and, on the other hand, entail the risk of injuring thegums by the edges and corners that are produced when they break off.

SUMMARY

The invention is therefore based on the object of further improving thecleaning effect of toothbrushes with pointed bristles and optimizing theservice life of the bristles with minimal potential for injury of thegums.

The object is achieved by a brush head for a toothbrush that includesfilaments that are pointed at one end, are led through clearances in abristle carrier and have a length of about 10 to 20 mm, the tips of thepointed filaments producing at least in certain regions a height profileother than that of a plane, and the ends of the pointed filaments thatare remote from the tips being melted. A production method includesleading filaments that are pointed at one end and have a length of about10 to 20 mm through clearances in a bristle carrier, the tips of thepointed filaments producing at least over certain regions a heightprofile other than that of a plane, and melting the ends of the pointedfilaments that are remote from the tips. Advantageous developments ofthe invention are provided by the dependent claims, the description andthe drawings.

The invention is based on the finding that the cleaning effect ofpointed filaments can be optimally used with minimal wear if the pathwhich the pointed filaments cover during use as intended is restricted.This possibility exists in the case of electric or manual toothbrusheson which the brush head or the bristle carrier, and with it thebristles, is set in motion and generally only a minimal additionalmanual cleaning movement is performed. In the case of electrictoothbrushes, the path of the pointed filaments or the tips that iscovered during use can therefore be controlled and restricted well bythe arrangement of the filaments on the bristle carrier. According tothe invention, the pointed filaments are arranged on the bristle carrierin such a way that, during the operation of the electric toothbrush,their tips cover at most a predetermined maximum path d_(max). The restof the bristle carrier may be provided with conventional bristles and/orfurther cleaning elements, for example soft-elastic elements.Conventional bristles and/or further cleaning elements may also bearranged between the pointed filaments.

The high-frequency motion of the pointed filaments produces an optimumcleaning performance. The restriction of the path which the tips coverhas the effect of minimizing the wear of the bristles, so that the riskof injury to the gums is also kept low.

With preference, the maximum path d_(max) of the tips is 5 mm, withparticular preference 3 mm. These distances correspond to the typicaldimensions of relatively large spaces between the teeth or of the teeth.If these maximum values are taken as a basis, the bristles move withinthe structures in the set of teeth. This allows in particular the finestfissures on the tooth surface and the interdental spaces to be reachedwell. It is also possible to reduce what is known as a “whiplash effect”when brushing over the spaces between the teeth perpendicularly to theiralignment. In the case of the “whiplash effect”, the intrinsicflexibility of the pointed filaments causes them to bend when they meetobstacles, such as the transition between two teeth, and lash forwardlike a whip when there is further movement, making the filaments undergoconsiderable stress.

The filaments may be pointed at one end or at both ends. They may alsobe colored, at least in the region of the tip. The color variation alsoprovides the user with a visible indication of the wear of the brush,for example if the color washes out over time.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is explained in more detail below with reference to thedrawings, in which, purely schematically:

FIGS. 1 a, 1 b respectively show three teeth in side view and plan viewto illustrate the desired movements;

FIG. 2 shows a brush head with a bristle carrier rotatably connected toit, with conventional bristles and pointed filaments;

FIG. 3 shows a brush head with a bristle carrier pivotable about thelongitudinal axis, with conventional bristles and pointed filaments;

FIG. 4 shows a brush head with a vibrating bristle carrier withconventional bristles and pointed filaments;

FIGS. 5 a-c show a brush head with a multipart bristle carrier;

FIGS. 6 a-d show preferred arrangements of clusters of pointed filamentson a brush head;

FIG. 7 shows a bristle carrier with clusters of pointed filaments;

FIG. 8 shows a bristle carrier with clusters of pointed filaments andconventional bristles;

FIGS. 9 a, 9 b respectively show a conventional bristle and a pointedbristle;

FIGS. 10 a-e show clusters of pointed filaments with various shapes;

FIGS. 10 f, 10 g show clusters of pointed filaments with variousprofiles;

FIGS. 11 a-e show brush heads in side view with various profiles of thepointed filaments;

FIG. 12 shows a brush head with clusters of bristles according to FIG.10 a;

FIGS. 13 a, 13 b show a brush head with clusters of bristles with softelements;

FIG. 14 a shows a receiving tank filled with pointed filaments, and FIG.14 b is an enlarged view of a section of the receiving tank as shown inFIG. 14 a; and

FIG. 15 a shows pushing means for pushing clusters of filaments througha bristle carrier and further parts off an AFT machine, and FIG. 15 b isan enlarged view of a section of FIG. 15 a.

DETAILED DESCRIPTION OF EMBODIMENTS

FIGS. 1 a, b show three teeth 1, standing in a row of teeth, withinterdental spaces 2 lying in between, respectively in side view andplan view. Examples of brush heads 3 with pointed filaments 5 areprovided by the other figures.

With pointed filaments 5, preferably small movements along the row ofteeth in the direction x and rather greater movements transverselythereto, i.e. in the direction Y, are performed in the plane of theteeth or in the direction Z perpendicular to the plane of the teeth.Excessive movements along the x direction are to be avoided, since theyare accompanied by great mechanical loading of the pointed filaments 5(whiplash effect). Consequently, the desired movements of the pointedfilaments 5 extend over the entire width b1 of the interdental spaces 2and over a strip of the width b2 and b3, respectively, along the flanks1 a, 1 b of the teeth. The width b1 is typically about 2 mm, the widthb2, b3 in each case about 5 mm.

In order to achieve an improved cleaning effect in comparison withmanual cleaning, the brush head 3 is driven in such a way that thepointed filaments 5 achieve more than 1000 cleaning movements perminute, but preferably more than 5000 movements. In the case of manualcleaning, significantly fewer than 1000 movements are achieved duringthe entire cleaning process. For each movement, the tip 5 a of a pointedbristle covers a distance d with respect to the stationary set of teeth(i.e. without overlaying a movement that may possibly be performedmanually). In order not to subject the pointed filaments 5 to excessiveloading under this high-frequency back and forth motion on the toothsurfaces and in particular when changing between tooth surface 1 a, 1 band spaces between the teeth, the path d of the tips 5 a of thefilaments 5 is less than a predetermined maximum path d_(max), which ispreferably 3 mm. These values correspond approximately to the size oflarge spaces 2 between the teeth, which can consequently be optimallycleaned without damaging the tips 5 a. The control and restriction ofthe movements of the tips 5 a has the effect of reducing the risk ofinjuries to the gums.

In an advantageous development, the maximum path d_(max) of the tips 5 adepends on the direction of movement, the maximum path d_(max,long) inthe longitudinal direction L of the brush head 3 preferably being lessthan the maximum path d_(max,trans) transversely thereto. Thelongitudinal direction L of the brush head 3 corresponds during useapproximately to the direction x of the row of teeth in which themovements of the bristles are preferably to be restricted because of thetooth-to-tooth transition and the accompanying loading of the bristles.This makes allowance for the geometry of the set of teeth and allows amovement along the spaces 2 between the teeth, i.e. in the Y and Zdirections, with a greater deflection than transversely thereto. Withpreference, d_(max,long) is 3 mm (X direction) and d_(max,trans) is 5 mm(Y, Z directions).

FIGS. 2-4 and 5 a-c show various examples of brush heads with a bristlearrangement of conventional bristles 6 and pointed filaments 5. Thebristles 5, 6 are respectively arranged in clusters 5′, 6′ on a bristlecarrier 4. The clusters 6′ of conventional bristles 6 are symbolized byan empty circle and the clusters 5′ of pointed filaments 5 aresymbolized by a circle with a dot.

In the case of the brush head 3 represented in FIG. 2, the bristlecarrier 4 is connected to the brush head 3 such that it can rotate backand forth about an axis of rotation D running perpendicularly to thebristle carrier 4. For this purpose, a suitable drive is present (notrepresented here). During operation, a maximum angle of rotation α isachieved. The pointed filaments 5 are arranged on the bristle carrier insuch a way that the following applies for the maximum distance r_(max),of their exit points on the bristle carrier from the axis of rotation D:r_(max)=d_(max)·180°:(πα), where d_(max) is the maximum path mentionedat the beginning. By approximation (distance between the points ofinflection instead of length of the arc), the following applies:r_(max)=d_(max):(2 sin(α/2)). Preferably, d_(max)=3 mm.

Devices with angles of rotation of up to 70° are currently on themarket. The diameter of the brush head 3 is generally less than 20 mm.The movement of the tips 5 a increases with the radius or the distancefrom the axis of rotation. The following table gives some values for thepath, calculated in dependence on the angle of rotation and the radius.The figures for the path that are shown with a gray background belong tothe pairs of radius/angle-of-rotation values that are permissibleaccording to the invention for d_(max)=3 mm (d_(max)=distance betweenthe points of inflection).

The table shows that, in the case of small angles of rotation, inprinciple the entire brush head 3 can be provided with pointed filaments5 and that, in the case of large angles of rotation, only a centralsegment 7 should be provided with pointed filaments 5.

FIG. 3 shows a brush head 3, which is pivoted about its longitudinalaxis L during operation, so that the brush head 3 performs a rockingsideward motion. The brush head 3 thereby passes over an angle β. Thefollowing applies for the maximum distance l_(max) of the tips of thepointed filaments from the pivot axis L: l_(max)=d_(max)·180°:(πβ) orl_(max)=d_(max):(2 sin(β/2)) (distance between the points ofinflection), where d_(max) is the maximum path mentioned at thebeginning. Preferably, d_(max)=3 mm.

In connection with pointed filaments 5, the rocking sideward motion isparticularly appropriate. With this type of toothbrush, during use thepointed filaments 5 move along the interdental spaces 2. The directionof movement that is less desired for the bristles and the gums isexcluded for the pointed filaments 5. In the case of this movement, themaximum path covered by the tips should likewise be less than 3 mm. Theangle of rotation can consequently be fixed on the basis of thefollowing table in dependence on the distance of the tips from the pivotaxis. The figures for the path that are shown with a gray backgroundbelong to the pairs of distance/pivoting-angle values that arepermissible according to the invention for d_(max)=3 mm. In the case ofan average distance of 12 mm, the angle of rotation of the brush headshould be chosen to be not greater than 15°.

FIG. 4 shows purely schematically a brush head 3, which vibrates in twodirections S1, S2 transversely to the longitudinal direction L. In thecase of this variant of movement, the brush head geometry has lessinfluence on the deflection of the conventional bristles 6 and pointedfilaments 5. The size of the deflection can be determined by choice ofthe electric current, motor and/or vibration generators. The directionof the deflection can be influenced by a special construction of thebrush handle, for example stiffening in the vertical direction, andadditional damping measures. Since the deflection of the brush head 3,and with it the tips of the pointed filaments 5, preferably follows theinterdental spaces 2, the toothbrush is preferably intended to have agreater lateral deflection in the direction S1 than a verticaldeflection in the direction S2. Deflections of less than 3 mm here alsoproduce a very gentle action and stimulation of the gums.

FIGS. 5 a-c show brush heads 3 in the case of which a rotationalmovement is combined with other types of movement. If a mechanicalmovement, for example rotation, is performed with an electrictoothbrush, vibration is also produced in any event. In the presentexamples, the bristle carrier 4 is of a multipart form. A round, firstcarrier element 4 a is connected to the brush head 3 rotatably about theaxis of rotation D (cf. FIG. 2). It is provided with conventionalbristles 6. At least one further carrier element 4 b is firmly connectedto the brush head 3 and provided with pointed filaments 5. Underrotation of the part 4 a, it is made to vibrate. In FIG. 5 a, thisfurther carrier element 4 b is in front of and behind the rotatingcarrier element 4 a in the longitudinal direction L; in FIG. 5 b, it isonly behind it and in FIG. 5 c it is only in front of it. The movedcarrier element 4 a with conventional bristles 6 undertakes the surfacecleaning and the co-vibrating, only indirectly mechanically movedcarrier element 4 b with the pointed filaments 5 undertakes theinterdental cleaning and the cleaning of very small structures. Insteadof rotating the first carrier element 4 a, it may also be pivoted aboutthe longitudinal axis.

FIGS. 6 a-d show examples of the arrangement of the pointed filaments 5on the bristle carrier 4. The pointed filaments 5 are first groupedtogether in clusters 5′. In the present case, these are circular incross section, but may also have some other shape, for example asrepresented in FIGS. 10 a-e. In the case of the brush head 3 accordingto FIG. 6 a, the clusters 5′ are grouped together in rows 9, which runtransversely to the longitudinal direction L. This arrangement is usedwith preference in the case of bristle carriers 4 which can pivot aboutthe longitudinal axis L or vibrate in this direction, since the rows 9coincide there with the running direction of the clusters 5′. In thecase of the example from FIG. 6 b, the bristle clusters 5′ are arrangedon arcs of a circle 10. This arrangement is used with preference in thecase of rotating bristle carriers 4. There are two inner circles ofbristle clusters 5′ with pointed filaments 5, the maximum radius ofwhich is r_(max). In both cases, the active region of the pointedfilaments 5 can consequently be spatially restricted well.

FIG. 6 c shows an example of a bristle arrangement with mixed clusters5′, 6′ of pointed filaments 5 and conventional bristles 6 on a roundbristle carrier 4 with a radius r_(max). The mixed bristle arrangementhas the advantage that the pointed filaments 5 have more freedom ofmovement and, in spite of bending on the tooth structures, cannot becomejammed in one another during use. In principle, the pointed filaments 5should be given more freedom of movement than the conventional bristles6. In particular at the outer limits, i.e. for arrangements in which thebristle tips cover approximately the maximum distance d_(max), such amixture with conventional bristles is advantageous.

FIG. 6 d shows a bristle arrangement in which the clusters 5′ of pointedfilaments 5 are arranged in segments 11 in the form of arcs of a circle.This arrangement corresponds substantially to FIG. 6 b and is likewisesuitable for rotating brushes.

Instead of arranging bristle clusters 5′ with a round cross section asdescribed in groups (rows, circles, segments), bristle clusters 5′ witha correspondingly adapted cross section may also be used (see FIGS. 11a-e).

In order that the pointed filaments 5 can move freely and theinterdental spaces 2 are not clogged, the individual clusters 8 arepreferably spaced sufficiently apart from one another. Since, in thecase of certain embodiments, the tips cover different distances independence on their location on the bristle carrier 4, the minimum holespacing x between neighboring clusters 8 is fixed in dependence on thepath covered. FIG. 7 shows an example of a rotating bristle carrier 4,of which only a centrally arranged pair of bristle clusters 8 and aperipherally arranged further pair of bristle clusters 8′ are shown forthe sake of overall clarity. The minimum spacings x1 near the axis ofrotation D are smaller than the minimum spacings x2 further away fromthe axis of rotation D.

Since, in the case of certain embodiments it is only appropriate toarrange the pointed filaments at a suitable position on the surface ofthe brush head, other types of filaments can be used at the positionswhich are not suitable. Conventionally rounded-off bristles, whichconsist for example of polyester PBT or polyamide PA, may be used inparticular for the surface cleaning of the tooth surface. If a massagingeffect of the gums is additionally required, soft rubber-elasticelements in the form of bristles, lamellae or other formations ofthermoplastic elastomer TPE may be additionally molded or inserted. FIG.8 shows an example of a bristle carrier 4 with such a mixed bristlearrangement comprising pointed filaments 5 within a central area with aradius r_(max) and peripherally arranged conventional bristle clusters6.

FIGS. 9 a, b explain the dimensioning of the conventional bristles 6 andthe pointed filaments 5. The conventional bristles 6 outlined in FIG. 9a have over their length a substantially constant nominal diameterΔ_(nom) (diameter at the thickest point of the bristle), which is forexample 0.15 to 0.25 mm. The tip 6 a of the bristle is rounded off.

In order to minimize the potential for injury in the case oftoothbrushes with high-frequency motions and maximize their lifetime,special requirements are imposed on the geometry and the nature of thepointed filaments 5. The pointed filaments 5 outlined in FIG. 9 blikewise have a constant diameter over a region of their length, forexample likewise a nominal diameter of 0.15-0.25 mm. Toward the tip 5 a,the bristle 5 tapers, beginning at a distance a from the tip 5 a.Measured from the tip 5 a, the diameter at the corresponding pointcorresponds for example to the following values:

Distance % of the nominal diameter (mm) Mean value Tolerance range 0.1 8%  5-15% 1 25% 15-35% 2 45% 30-60% 3 60% 50-80% 4 75% 60-90% 5 80%70-90% 6 85% >75% 7 90% >80%

In order to achieve adequate flexibility of the filaments, their lengthfrom where they leave the brush head is chosen to be between 7 and 13mm. In order to ensure adequate stability of the individual filamentsunder high-frequency motion, over 75% of the nominal diameter is leftover a large part of the length. The table presented above shows thatthe pointing of the filaments predominantly takes place over the last 4to 5 mm. With this configuration, the tip 5 a can optimally reach thesmallest fissures and interdental spaces 2 with adequate filamentstability.

For the pointed bristles, polyamide is preferably used, or elsepolyester (PBT). The pointing process is based on the reduction of thediameter by means of a chemical process. Depending on the length of timefor which the bristle remains in the chemical substance, the plasticdecomposes and the diameter is reduced. In this way, the shape of thepoint can be influenced.

FIGS. 10 a-e show examples of the shape of clusters 5′ of pointedfilaments 5. Such a cluster 5′ does not necessarily have to have a roundshape. Substantially triangular (FIG. 10 a), substantially rectangular(FIG. 10 b), elliptical (FIG. 10 c), arcuate (FIG. 10 d) or other shapes(FIG. 10 e) come into consideration. The elongate shapes according toFIGS. 10 a-c are appropriate in particular for pivotable toothbrushesand may be used instead for the arrangement of round bristle clusters inrows (cf. FIG. 12, in which a mixed bristle arrangement of normalbristle clusters 6′ with round cross section and clusters 5′ of pointedfilaments 5 with the shape represented in FIG. 10 a is shown). The shapeshown in FIG. 10 d is particularly advantageous for rotatingtoothbrushes.

FIGS. 13 a-b show another embodiment of a mixed bristle arrangement ofnormal bristle clusters 6′ with round cross section and clusters 5′ ofpointed filaments 5. In this embodiment, a set of the clusters 5′ isreplaced by a pair of soft rubber-elastic elements 12.

The greatest extent e is preferably approximately 3 mm and consequentlycorresponds to a large interdental spacing. If too many filaments aregrouped together in each cluster 5′, this can cause unnecessarystiffening of the individual filaments 5 and make penetration into theinterdental spaces 2 more difficult. A cluster 5′ therefore preferablycontains fewer than 80, with particular preference fewer than 50,pointed tips 5 a of the filaments 5. In this case, depending on theproduction technique, each filament may have one or two pointed tips 5a. Certain filaments also have a round tip and a pointed tip 5 a.

FIGS. 10 f+g show examples of the height profile of the bristle clusters5′ from FIGS. 11 d and 11 e, respectively. Such non-constant heightprofiles are realized with preference by the AFT or IMT method.

FIGS. 11 a-e show brush heads 3 in side view, in the case of which thetips 5 a of the pointed filaments 5 form different profiles. FIGS. 11a-d relate to pivotable brush heads, FIG. 11 e to a rotating brush head.

For fabrication reasons, the flat profile shown in FIG. 11 a can beproduced most simply. In this case, just one basic filament length isused, adopting conventional punching technology. Approximately 80% ofthe filament ends are positioned within the height range Δh of 4 mm inlatitude. Different filament lengths within these limits are desired toa certain extent, since they consequently ensure easier interdentalpenetration than in the case of an exactly equal length, as is producedwhen cutting conventional bristles. Individual, prominently projectingfilaments should be avoided, however, since they entail the risk ofinjuring the gums, in particular under high-frequency motion.

FIG. 11 b shows a brush head in the case of which a profile shapedeviating from a plane is produced by means of conventional punchingtechnology with two different basic lengths of the pointed bristles.Usually, both ends of the filaments are pointed. The latter are bent ina U-shaped manner to create bristles. For this reason, the pointedbristles cannot be cut, and with this technology there is a limitationto different planes, here planes E1 and E2. Within the planes E1, E2,height variations are in turn possible within the height range Δh ofapproximately 4 mm. There is greater freedom with filaments pointed atone end.

If, for the reasons already mentioned, different filament types arecombined, the pointed filaments 5 for the interdental cleaning arepreferably longer than conventionally rounded-off bristles or massagingelements. The different types of bristles are preferably used in thebristle carrier in place of the other respective type or types ofbristles. Alternatively, the bristle carriers 4 could be of a multipartform, separately provided with bristles and subsequently joinedtogether.

For the production of the brush heads 3 according to the invention, theAFT (Anchor Free Tufting) method or IMT (In Mold Tufting) method isappropriate in particular. The AFT method is described for example inEP-A 0 972 464. The IMT method is described for example in EP-A 0 795711 and EP-A 0 346 646. Unlike in the case of conventional tufting, thepointed filaments 5 are in this case only pointed at one end when theyare fed to the AFT or IMT machine. The length of the filaments isbetween 10 and 20 mm. As shown in FIGS. 14 a, 14 b, the filaments 5 arepreferably inserted into the receiving tank 13 with the tips 5 adownward. There is consequently no need for later reorientation withinthe AFT or IMT machine. The filaments 5 are pushed by the pushing means17 on the pointed side 5 a through the bristle carrier 4 (in the case ofIMT through the transporting inserts) as shown in FIGS. 15 a, 15 b. Forthis purpose, as also shown in FIG. 13 b, the bristle carrier hasclearances 14 for the bristles. The non-pointed side is cut and, asknown, subsequently melted to form a melted end 15. If the bristlecarrier is not in one piece with the brush head, the two parts aresubsequently connected to each other, preferably by means of ultrasonicwelding. The FIGS. 15 a, 15 b further show a support 19 for the pushingmeans 17, a guidance plate 21, a carrier means 23 and a filamentguidance 25 of an AFT machine as disclosed in EP 0 972 464.

The AFT or IMT method makes simplified production of the pointedfilaments possible, since they only have to be pointed at one end.Furthermore, by corresponding configuration of the pushing means, theindividual clusters are profiled, for example for better interdentalpenetration. Examples of this are shown in FIGS. 11 c-e and also inFIGS. 10 f+g (profiling of the individual clusters). This is notpossible with the conventional tufting technology. Since the filamentsare cut after the profiling, only one filament length has to beprovided. The bristles can be cut to the desired length. By contrastwith this, in the case of conventional tufting technology, a number ofmaterial lengths have to be used to create a topology other than that ofa plane.

The AFT and IMT methods consequently have great advantages for theproduction of the toothbrushes according to the invention, since alargely unrestricted shape of the bristle clusters is made possible.This allows the path covered by the tips during use to be controlledparticularly well. The production method can also be advantageously usedfor the production of manual toothbrushes.

What is claimed is:
 1. An electric toothbrush comprising a brush headmoving in two directions S1, S2 transversely to its longitudinaldirection L, with a bristle carrier, wherein the bristle carrier has amixed filament arrangement containing: pointed filaments with taperedtips arranged in clusters containing a plurality of pointed filamentsonly, conventional filaments with a substantially constant diameter androunded-off tips arranged in clusters containing a plurality ofconventional filaments only and wherein the pointed filaments arearranged on the bristle carrier in such a way that, during the operationof the electric toothbrush, their tips cover at most a predeterminedmaximum path of 3 mm.
 2. The electric toothbrush as claimed in claim 1,wherein the toothbrush head has a greater lateral deflection in thedirection S1 than a vertical deflection in the direction S2.
 3. Theelectric toothbrush as claimed in claim 1, wherein the brush head isdriven in such a way that the filaments perform at least 5000 movementsper minute.
 4. The electric toothbrush as claimed in claim 1, whereinthe deflection of the filaments in a direction perpendicular to thebristle carrier is less than the deflection of the filaments in alateral direction.
 5. The electric toothbrush as claimed in claim 4,wherein the deflection of the filaments in the direction perpendicularto the bristle carrier is less than 3 mm and the deflection of thefilaments in the lateral direction is less than 5 mm.
 6. The electrictoothbrush as claimed in claim 1, wherein the pointed filaments have anominal diameter of 0.15 to 0.25 mm and the diameter of the pointedfilaments is greater than 75% of the nominal diameter up to a distanceof 5 to 6 mm from the tip and is smaller as the distance becomes less.7. The electric toothbrush as claimed in claim 6, wherein the diameterof the pointed filaments measured at the distance of 1 mm from the tipranges from 15-35% of the nominal diameter.
 8. The electric toothbrushas claimed in claim 6, wherein the diameter of the pointed filamentsmeasured at the distance of 2 mm from the tip ranges from 30-60% of thenominal diameter.
 9. The electric toothbrush as claimed in claim 6,wherein the diameter of the pointed filaments measured at the distanceof 4 mm from the tip ranges from 60-90% of the nominal diameter.
 10. Theelectric toothbrush as claimed in claim 1, wherein the clusters withpointed filaments contain fewer than 80 tips, with particular preferencefewer than 50 tips.
 11. The electric toothbrush as claimed in claim 1,wherein the clusters with pointed filaments have a maximum width e ofabout 3 min.
 12. The electric toothbrush as claimed in claim 1, whereinthe clusters with pointed filaments have a circular cross section. 13.The electric toothbrush as claimed in claim 1, wherein the clusters withpointed filaments have a non-round shape.
 14. The electric toothbrush asclaimed in claim 13, wherein the non-round shape includes at least oneof substantially triangular, substantially rectangular, elliptical or anarcuate shapes.
 15. The electric tooth brush as claimed in claim 1,wherein the clusters with pointed filaments form a non-constant heightprofile.
 16. The electric toothbrush as claimed in claim 1, wherein theclusters are arranged on the bristle carrier one behind the other in thedirection of movement.
 17. The electric toothbrush as claimed in claim1, wherein at least 80% of the pointed filaments have a length, measuredfrom the exit point on the bristle carrier, from the interval [L, L+4mm], where L is a predetermined length.
 18. The electric toothbrush asclaimed in claim 1, wherein pointed filaments have different lengths andthe tips of at least 80% of the pointed filaments are positioned withrespect to the height profile with a height range of about 4 mm.
 19. Theelectric toothbrush as claimed in claim 1, wherein the pointed filamentsare longer than the conventional filaments.
 20. The electric toothbrushas claimed in claim 1, wherein the bristle carrier is provided withrubber elastic cleaning elements.
 21. The electric toothbrush as claimedin claim 20, wherein the pointed filaments are longer than the rubberelastic cleaning elements.
 22. The electric toothbrush as claimed inclaim 20, wherein the rubber elastic cleaning elements are arrangedbetween the pointed filaments.
 23. The electric toothbrush as claimed inclaim 1, wherein conventional filaments are arranged between the pointedfilaments.
 24. The electric toothbrush as claimed in claim 1, whereinthe pointed filaments are colored in the region of the tip.
 25. Anelectric toothbrush comprising a vibrating brush head with a bristlecarrier, wherein the bristle carrier has a mixed filament arrangementcontaining: pointed filaments with tapered tips arranged in clusterscontaining a plurality of pointed filaments, conventional filaments witha substantially constant diameter and rounded-off tips arranged inclusters containing a plurality of conventional filaments and whereinthe pointed filaments are arranged on the bristle carrier in such a waythat, during the operation of the electric toothbrush, their tips coverat most a predetermined maximum path of 3 mm.
 26. An electric toothbrushcomprising a vibrating brush head with a bristle carrier, wherein thebristle carrier has a mixed filament arrangement containing: pointedfilaments with tapered tips arranged in clusters containing a pluralityof tips, and conventional filaments with a substantially constantdiameter and rounded-off tips arranged in clusters containing aplurality of tips, wherein the brush head is driven in such a way thatthe filaments perform at least 5000 movements per minute.
 27. Anelectric toothbrush comprising a vibrating brush head with a bristlecarrier, wherein the bristle carrier has a mixed filament arrangementcontaining: pointed filaments with tapered tips arranged in clusterscontaining a plurality of tips, and conventional filaments with asubstantially constant diameter and rounded-off tips arranged inclusters containing a plurality of tips, wherein the pointed filamentsare longer than the conventional filaments.